How does Turbopack cache build results?
Turbopack caches build results at the level of each module and each step of its processing, storing intermediate and final artifacts in a local persistent cache. This allows it to reuse previously computed data and rebuild only what actually changed.
How caching works under the hood
- Storing results on a per-module basis Each file (JS, TS, CSS, etc.) is cached after analysis, transformation, and dependency computation. If a file has not changed, Turbopack simply takes its result from the cache.
- Integrity control via hashes File contents and environment parameters are hashed. If the hash matches, no rebuild is triggered for that module.
- Caching every stage of the pipeline Turbopack stores not only the final module, but also the intermediate steps: AST parsing, import resolution, transformations, plugin results, and so on.
- Incremental graph recalculation When one file changes, only the related nodes of the dependency graph are recalculated, not the whole project.
What this gives you
| Mechanism | Benefit |
|---|---|
| Module caching | rebuilding is not performed unnecessarily |
| Hash checks | excludes recalculating unchanged parts |
| Caching intermediate stages | saves CPU on complex transformations |
| Incremental model | only the necessary minimum is updated |
Summary
Turbopack caches the build deeply and stage by stage, using hashes and a modular structure to reuse the maximum amount of results and rebuild only the affected parts of the project. This is exactly the basis of its high speed on subsequent updates.
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